The members did three rounds of finger-prick assessments at house between June 20 and Sept. 28, in keeping with a news release from the Imperial School London. Fairly than increase immunity, the variety of folks with antibodies fell from 6% at first of the examine to 4.4% on the finish – a drop of about 26.5%, the discharge mentioned.
The decline was highest amongst folks 75 and older and lowest in folks 18-24. Well being care employees confirmed no decline in antibodies.
“This very massive examine has proven that the proportion of individuals with detectable antibodies is falling over time,” mentioned Professor Helen Ward, one of many lead authors of the report. “We don’t but know whether or not this may depart these folks prone to reinfection with the virus that causes COVID-19, however it’s important that everybody continues to comply with steering to cut back the danger to themselves and others.”
Researchers cautioned, nevertheless, that the examine has limitation and that the identical teams of individuals weren’t essentially examined in every spherical, so there could also be an opportunity that much less contaminated folks had been examined in every spherical.
The findings are a blow to scientists who assume herd immunity will ultimately carry down the coronavirus.
Herd immunity happens when a big a part of a inhabitants turns into proof against a illness by creating antibodies, both by vaccination or by turning into contaminated.
Whereas each single particular person might not be immune, the group as an entire has safety. Researchers have mentioned 50% to 67% of the inhabitants would have to be resistant earlier than herd immunity kicks in and the an infection charges begin to go down.
Professor Paul Elliott, director of the Imperial School London program, emphasised that scientists nonetheless don’t understand how a lot — if any — immunity is imparted by having COVID antibodies.
“Testing constructive for antibodies doesn’t imply you might be proof against COVID-19,” he mentioned. “It stays unclear what degree of immunity antibodies present, or for the way lengthy this immunity lasts. If somebody assessments constructive for antibodies, they nonetheless have to comply with nationwide tips together with social distancing measures, getting a swab check if they’ve signs and sporting face coverings the place required.”